The notion of packing food in reusable jars began in the 1870s, but in the Depression era, companies began decorating these glass containers with attractive designs and characters as an incentive to buy the products. With a new process called silk-screening, glasses could be decorated with remarkable precision.
Kraft was among the first to decorate its jars, stenciling small glass containers filled with cheese spread with gingham patterns, stripes, stars, and flowers. Kraft called the glasses Swanky Swigs. Around the same time, sour cream and cottage cheese jars appeared printed with Mickey Mouse, Donald Duck, and other Disney characters. Eventually, supermarket shelves were stocked with jars of food decorated with colorful and whimsical designs. Because each glass was part of a series, the customer who was loyal to one brand could create an entire set. Glass giveaways are now quite collectible; to find the greatest supply, search at antiques shows, specialty dealers, and online auction sites.